1. Technical Field
The present disclosure relates to an imaging device. More specifically, the present disclosure relates to an imaging device that has a photoelectric conversion unit including a photoelectric conversion film and stacking on a semiconductor substrate.
2. Description of the Related Art
A multilayer imaging device is proposed as an MOS (Metal Oxide Semiconductor) imaging device. In the multilayer imaging device, a photoelectric conversion unit including a photoelectric conversion film is stacked on a topmost surface of a semiconductor substrate, and an electric charge generated through photoelectric conversion in the photoelectric conversion film is accumulated in an electric charge accumulation region (called “floating diffusion”). The imaging device reads out the accumulated electric charge by using a CCD (Charge Coupled Device) circuit or a CMOS (Complementary MOS) circuit in the semiconductor substrate. For example, Japanese Unexamined Patent Application Publication No. 2009-164604 discloses such an imaging device.
In the field of imaging device, there are demands for a noise reduction. In particular, there are demands for a reduction of kTC noise generated at the time of reset (also referred to as “reset noise”).